This guide explains the one-port TCP reachability check and why an accepted socket is only one layer of DC++ hub diagnosis.
Usage
- Open TCP Connect and enter the public hostname, IP address, or hub URL in Host Or Address.
- Enter the exact TCP Port published for the hub.
- Select Test Connection and review the connection outcome, duration, resolved addresses, and detail.
Concrete Example
For dchub://hub.example.net:411, test port 411. If the row is open, the hublist server completed a TCP connection to that address and port. It has not yet proved that the listener speaks NMDC or accepts a user login.
Interpretation
Open means the socket connected. Closed normally means the host rejected the connection because no listener was available. A timeout can indicate filtering, routing, incorrect forwarding, or an offline target. Use duration only as connection timing.
Troubleshooting
- Ping Works, TCP Fails: Check the listener, host firewall, NAT, and provider rules.
- TCP Works, Hub Fails: Select the expected protocol in Protocol Test.
- Secure Hub Fails: Inspect the TLS port and certificate with TLS Certificate.
- Wrong Resolved Address: Correct public DNS with DNS Overview before retesting.
Icon Reference
| Icon | Label | What It Does |
|---|---|---|
| Test Connection | Test Connection submits one public host and TCP port. | |
| Complete | Complete marks a finished socket attempt. | |
| Review Output | Review Output marks a failed or incomplete connection that needs another check. | |
| Open Help | Open Help opens this guide from the TCP Connect panel. |